Dialkyl carbonates have attracted much attention from the viewpoint of sustainable chemistry because they are useful intermediates and solvents and can be synthesized from renewable resources. One promising synthesis method of the dialkyl carbonates is the reaction of CO2 with the corresponding alcohols. Direct synthesis of diethyl carbonate and dipropyl carbonate from ethanol + CO2 and 1-propanol + CO2 was promoted remarkably by the combination of acetonitrile hydration. The yield based on CO2 reached 42 and 33% for diethyl carbonate and dipropyl carbonate, respectively. All the reactions were catalyzed by CeO2 as a heterogeneous catalyst. It is characteristic that the combination with in situ dehydration enabled the conversion of low pressure CO2 to dialkyl carbonate. (C) 2010 Elsevier B.V. All rights reserved.